Alpha-lipoic acid
Dihydrolipoic acid; Lipoic acid; Lipolate; Thiotic acid
Alpha-lipoic acid is an antioxidant made by the body. It is found in every cell, where it helps turn
glucose into energy. Antioxidants attack "free radicals," waste products created when the body
turns food into energy. Free radicals cause harmful chemical reactions that can damage cells,
making it harder for the body to fight off infections. They also damage organs and tissues.
Other antioxidants work only in water (such as vitamin C) or fatty tissues (such as vitamin E).
But alpha-lipoic acid is both fat and water soluble. That means it can work throughout the body.
Antioxidants in the body are used up as they attack free radicals. But evidence suggests alphalipoic acid may help regenerate these other antioxidants and make them active again.
In the cells of the body, alpha-lipoic acid is changed into dihydrolipoic acid. Alpha-lipoic acid is
not the same as alpha linolenic acid, which is an omega-3 fatty acid that may help heart health.
There is confusion between alpha-lipoic acid and alpa linolenic acid because both are sometimes
abbreviated ALA. Alpha-lipoic acid is also sometimes called lipoic acid.
Diabetes
Several studies suggest alpha-lipoic acid helps lower blood sugar levels. Its ability to kill free
radicals may help people with diabetic peripheral neuropathy, who have pain, burning, itching,
tingling, and numbness in arms and legs from nerve damage. Researchers believe Alpha-lipoic
acid helps improve insulin sensitivity.
Alpha-lipoic acid has been used for years to treat peripheral neuropathy in Germany. However,
most of the studies that have found it helps have used intravenous (IV) alpha-lipoic acid. It's not
clear whether taking alpha-lipoic acid by mouth will help. Most studies of oral alpha-lipoic acid
have been small and poorly designed. One study did find that taking alpha-lipoic acid for
diabetic neuropathy reduced symptoms compared to placebo.
Taking alpha-lipoic acid may help another diabetes-related condition called autonomic
neuropathy, which affects the nerves to internal organs. One study of 73 people with cardiac
autonomic neuropathy, which affects the heart, found that subjects reported fewer signs of the
condition when taking 800 mg of alpha-lipoic acid orally compared to placebo.
Brain Function and Stroke
Because alpha-lipoic acid can pass easily into the brain, it may help protect the brain and nerve
tissue. Researchers are investigating it as a potential treatment for stroke and other brain
problems involving free radical damage, such as dementia. So far, there's no evidence to say
whether or not it works.
Other
Preliminary studies suggest alpha-lipoic acid may help treat glaucoma. But there is not enough
evidence to say for sure whether it works. In one study on aging skin, a cream with 5% lipoic
acid helped reduce fine lines from sun damage. Studies show ALA binds with toxic metals, such
as mercury, arsenic, iron, and other metals that act as free radicals. Preliminary studies also
suggest that ALA may play a role in managing other conditions including erectile dysfunction
and cancer. And preliminary studies suggest it may reduce complications associated with otitis
media (ear infections).
Dietary Sources
If you are healthy, your body makes enough alpha-lipoic acid. It is also found in red meat, organ
meats (such as liver), and yeast -- particularly brewer's yeast.
Available Forms
Alpha-lipoic acid supplements are available as capsules. Your health care provider can also give
it by injection.
How to Take It
Pediatric
Alpha-lipoic acid has not been studied in children, so it is not recommended for pediatric use.
Adult
Check with your doctor regarding dosing recommendations. Studies are mixed about whether or
not to take ALA with meals.
Precautions
Because of the potential for side effects and interactions with medications, you should take
dietary supplements only under the supervision of a health care provider.
Alpha-lipoic acid hasn't been studied in pregnant or breastfeeding women, so researchers don't
know if it's safe.
Side effects are generally rare and may include insomnia, fatigue, diarrhea, and skin rash.
Alpha-lipoic acid can lower blood sugar levels, so people with diabetes or low blood sugar
should take alpha-lipoic acid only under the supervision of their health care provider.
Animal studies suggest that people who don't get enough thiamine (vitamin B1) should not take
alpha-lipoic acid. B1 deficiency is associated with long-term alcohol abuse.
Possible Interactions
If you are being treated with any of the following medications, you should not use alpha-lipoic
acid without first talking to your health care provider.
Medications for diabetes
Apha-lipoic acid can combine with these drugs to lower blood sugar levels, raising the risk of
hypoglycemia or low blood sugar. Ask your provider before taking alpha-lipoic acid, and watch
your blood sugar levels closely. Your provider may need to adjust your medication doses.
Chemotherapy medications
Alpha-lipoic acid may interfere with some chemotherapy medications. Always ask your
oncologist before taking any herb or supplement, including alpha-lipoic acid.
Thyroid medications, Levothyroxine
Apha-lipoic acid may lower levels of thyroid hormone. Your provider should monitor blood
hormone levels and thyroid function tests closely.
Vitamin B1 (Thiamine)
Alpha lipoic acid can lower the level of vitamin B1 (Thiamine) in the body. This can be
particularly dangerous in alcoholics where malnutrition is often already present.
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https://www.mountsinai.org/health-library/supplement/alpha-lipoic-acid